Friction pump



April 1955 P. SCHLUMBOHM 2,706,016

FRICTION PUMP Filed May 10, 1951 2,706,016 FRICTION PUMP Peter Schlumbohm, New York, N. Y. Application May 10, 1951, Serial No. 225,620

1 2 Claims. ((1183-63) The invention refers to a friction pump for centrifuging fluids. The new pump of my invention is characterized by a plurality of discs of porous material which are arranged to rtate--in concentrically superposed spaced relationon the same shaft. The space between two directly adjacent superposed porous discs forms the centrifuging space in which the fluid is centrifuged towards the peripheral zone of the space. The pores of the discs form the only intake passage for the fluid to be pumped entering said centrifuging space.

The invention is illustrated by way of examples in the Fig. l-Fig. 4 of the accompanying drawings.

Fig. 1 shows a side view of the blower as arranged on the shaft of an electric motor, shown partly in view and partly in vertical section.

Fig. 2 also shows a side view of the blower and in the-same manner, but with a modification of details.

Fig. 3 shows another modification of a detail, in view.

Fig. 4 shows-in reduced scale-a view of the blower of Fig. 1 while in rotation, and also shows the possible arrangement of such a blower in a casing for deflecting the centrifugally ejected air.

My very first experiment was with two die-cut circles of 11 /2" diameter, spaced /2" from each other. The

pattern of the two rotating discs was as shown in Fig. 4. Each disc was deformed into the geometrical pattern of a cone and both discs together thus showed during rotation the geometrical pattern of a double cone with a small free space between the circumferential edges. This free space formed the ejector nozzle.

Such a rotor actually rides on the load. The air rushing in through the permeable paper walls partially breaks the vacuum in a very desirable way and the ejector nozzle never becomes a handicap as a throttle. Also by avoiding an extreme vacuum and by operating with a partial vacuum, the side walls of the pumping space are not brought too near to each other, which would limit the flow of air through said pumping space and which would cause flow resistance. The geometrical pattern of a double cone for the two rotating discs is ideal from the point of aerodynamics. Only a partial vacuum will produce this geometrical pattern. Using a porous material for these rotating discs and letting the pores of the material form the only intake passage for the fluid to be pumped is my way of producing and balancing such a partial vacuum.

In the application of the invention to air-blowers, where it is desirable not only to circulate air but also to filter the air, this arrangement is at the same time very effective to filter the air from dust when the air passes through these rotating discs of Filter Paper into the pumping s ace.

My further experiments showed that the control of the air flow and the etficiency of the apparatus could be greatly improved by providing what I call a stabilizer." This stabilizer is an additional disc, placed halfway between the two rotating air-intake discs. One must realize that the air entering through the two rotating outer discs meets head-on in the pumping space and thus creates eddying currents. These eddying currents result in an irregular air flow at the circumferential ejector nozzle, causing fluttering of the edges of the paper discs and resulting in noise. By introducing the stabilizer, the air which enters into the pumping space meets the rotating surface of the stabilizer and is deflected towards the ejector nozzle. Introducing such a stabilizer also makes it possible to double the spacing between the two outer discs. It was further found that this stabilizer was made still more workable by the greater stiffness produced bygiapplying more than one paper disc as stabilizer, for instance, as shown in Figure 1. a set nited rates i atent O ice of four paper discs. These four paper discs may be spaced from each other by thin spacers as shown in Figure 2. Furthermore, it was found that varied effects on the air flow of the pumped air could be obtained by making the stabilizer either of the same diameter as the outer disc, as shown in Figure l, or by making the stabilizer of a smaller diameter than the outer disc as shown in Figure 2 or by making the stabilizer of larger diameter as shown in Figure 3.

I found further that spacer discs of cork were most suitable, providing a good friction grip on the filter paper.

I further invented a special arbor for holding the rotor together and for mounting it on the shaft of a driving motor.

Explaining the details of Figure 1, will explain the details of the other figures.

In Figure 1, an arbor 1 is shown mounted and fixated bya set screw 2 on'the driving shaft 3 of an electric motor 4. k

The arbor 1 has one sleeve 5 which fits over the shaft 3. Joining this sleeve is a shoulder 6 and a shaft 7. The shaft 7 hasan outside thread 8 and a cover plate 9 which can be screwed on to this thread 8. Arranged at the shoulder 6 is the one filter paper disc 10, then follows a cork spacer 11, then follows the stabilizer 12, then follows another cork spacer 13, then follows the other air-intake disc 14 and they all are held together between the shoulder 6 and the cover plate 9.

In Figure 2, the same arrangement is shown except that three extra spacers 15 are arranged within the stabilizer 12. Alsonew in Figure 2 are stapling wires 16 which hold the entire rotor together so that the rotor may be offered as a new product on the market as an entity and replacement part. Such a rotor would comprise the outer discs, the spacers and the stabilizer.

One of the greatest advantages of my new blower is its safety, especially its safety for children. Following the invention, a material is chosen for the rotating discs which will not form a cutting edge. Moreover, in manufacturing these discs, I sandpaper the edge of the discs to make it completely non-cutting.

Another advantage is the cleanliness of the blower. The air-intake discs, due to their filtering effect, become dirtyand can be replaced by fresh filter paper discs. Replacing the rotor by a spare part rotor, such as shown in Figure 2, does away with the difficult job as now presented of cleaning the standard electric fan.

The rotor may bev installed in the casing of a vacuum cleaner as its air propelling element, its filtering element or both.

I claim as my'invention:

1. Friction pump for centrifuging fluids, comprising a rotatable shaft, a plurality of concentrically superposed porous discs so attached to said shaft that the pores of said discs form the only intake passage for the fluid to be pumped; the space between two directly adjacent superposed porous discs forming the centrifilging space in which the fluid is centrifuged towards the peripheral zone of said centrifuging space.

2. Friction. pump as claimed in claim 1, in which the porosity of the material of the discs is such that the pores offer enough flow resistance to throttle the flow of a gas passing through them, whereby a continuous partial vacuum is maintained in the centrifuging space when the gas is centrifuged towards the peripheral zone of that space.

References Cited in the file of this patent UNITED STATES PATENTS Wales Mar. 24, 1953 

